Psychology is a very interesting subject and since we’re talking about it, your post exhibits some core concepts of Narcissistic Personality Disorder.
#1: Inflated sense of self-importance: “I’m heterosexual and I’m the one flying flags who has bumper stickers on my car. Why? My young and locally employed LGBTQ friends and neighbors are afraid to.” Check 
#2: Lack of Empathy towards the opinions of others : “makes the comparison you make irrelevant at best, ridiculous in general, and deceitful at worst. “. Check
#3: Compelling need for admiration: “They appreciate being acknowledged by someone who has nothing to fear. So I do it.” Check
Your statement implies that LGBTQ individuals need your bumper stickers and your flags waving in order to have a happy and fulfilling existence ? What about other seemingly oppressed populations that could benefit from a champion such as yourself to stand up for them on the daily by flying flags and bearing bumper stickers? Maybe folks that drive crappy cars or people that don’t wear deodorant or agoraphobics or those who don’t like the color blue or people who prefer to work night shift or populations that are vegetarian or etc, etc, etc? How does one choose whose cause to champion and whose cause not to champion? As an individual who is a champion for causes, what is the criteria to determine which causes to support or not support? As an individual who is entitled to decide which causes you will defend, others with different views can also choose which causes they will support and as such are entitled to said beliefs as an American citizen.
Also, the statement that “‘Heterosexual folks’ ‘announce’ their gender or sexuality every day” implies that simply by going about one’s business is someone else’s business, or that by simply living their life someone is making a sociopolitical point, however unintended it may be, which is simply not the case. In fact, there is not a, to use your phrase, “hetero” flag, nor are there “hetero” bumper stickers. The need to proclaim sexual preferences or support of others sexual preferences via a visible flag or bumper sticker seems to be inviting questions, attention, possibly support or dissent, no? In fact, if it isn’t an issue, why bring attention to sexual preferences and then unwittingly potentially cause an LGBTQ individual be made to feel singled out or not “normal”? Isn’t pointing out the differences actually being harmful to those who are might perceive themselves as different?
What ever happened to simply being nice to people, not putting individuals who might not care what someone else’s sexuality is, in a position where they might feel uncomfortable and therefore want to avoid the uncomfortable situation altogether by simply avoiding others exhibiting similar behaviors?
Also, regarding the phrase “Kids are made to feel like they don’t fit in by people who tell them they aren’t normal”: isn’t it quite normal to feel abnormal at some point as a child of various ages? Actually, comparing oneself to others is a road block of life the majority of individuals will experience at some point and regardless of an individual actually telling the person they “aren’t normal” or not, it is based in the social comparison theory first developed by Leon Festinger in 1954. Therefore, the argument that pointing out concepts/thoughts/behaviors that are potentially to the detriment of a child and directing the child away from making inappropriate, abnormal, life-altering decisions at a young age is not scarring or harmful and is not the same as telling the child they “aren’t normal”. It is a form of guidance and the appropriate response until the child is old enough to fully comprehend the consequences of potentially life-altering decisions. Individuals that seek to undermine authority of the actual parents, teachers, other authority figures in the lives of a child by whispering in their other ear that the person in the actual position of authority is doing the child harm by simply guiding them in a manner until the appropriate time of life at which the child will be an adult, capable of fully understanding and/or bearing the consequences of their actions, is the individual responsible for causing turmoil and harm in the life of the child, not those intending to steer the child in the appropriate direction until the appropriate time. Interestingly, individuals who undermine a child’s parents/caregivers typically exhibit core behaviors of narcissistic behavior disorder and are the ones who are ultimately responsible for causing harm and distress and feelings of inferiority to the child.
In conclusion, here are a few points.
#1: Hero syndrome is a component of narcissistic personality disorder and many feel it is their right to impose this on the subset of their choosing for benefit of themselves through positive feedback.
#2: The logic that LGBTQ people need stickers and flags in order to feel supported is flawed at best, lethal at worst.
#3: Attention seeking behaviors will draw attention, whether wanted or unwanted so such behaviors should be avoided unless attention is so desired.
#4: Children need and are seeking appropriate guidance until they are fully capable of accepting responsibility for their actions which is (questionably) at the age adulthood and until then, the children deserve to focus on being children and steered away from sexually deviant behaviors. The right to direct the life of a child lies ONLY in the hands of the parents/caregiver and authority to do so may be desseminated only by the parents/caregivers.
#5: If defining sexually deviant behaviors as abnormal (as the very definition of such is stating) is a bad thing, then so be it.
Psychology can be very enlightening.
