Tattoo's are artistic expression. When properly designed and thought out, as with people who do full body art do- it is another form of expression like painting or dance. We all do it to a certian extent with our outer appearce, tattoos just do it to a more severe degree.
And as for the 'gay' thing I am going to ignore it. Because to steryotype someone is stupid enough- but to do so, then make assumptions about their sexuality based on outer apperance and baseless assumtions is just ridiculous and biggoted.