IDK about the first two, still learning it myself, but for your third bullet point:
Settings > Account Preferences > Show NSFW
This is a setting that's saved by your instance, not by Boost, so if you change it on one account it shouldn't affect the others. I think.
I don't want to be pedantic because I appreciate your astute analysis, but as a fan of classic movies, it's clear that this isn't an ad, but rather a t-shirt referring to a humorous line from Legally Blonde.
Unfortunately, the composition of the photograph omits the sleeves and neck of the shirt, and the design evokes the imagery and aesthetic of advertisements for 1960's drive-in theater concession stands, so it is easy to mistake it for an ad.
Ultimately, the main point of your comment, that the phrase is still difficult to read even though the words "Hot Dog" are grouped together, still stands.
Which then does work for this post...