I think it might well be a case of the grass is always greener. Rather than being disappointed with your own and thinking it's 'too small' (8x6.25 is what most would consider massive), you still think it could be better. It's essentially just semantics, but I think it's key in this case and once you manage to differentiate between 'not big enough' and 'not the biggest' everything'll be ok.
And as mentioned, porn almost certainly does play a part in things. Not just in the other sizes on display, but the level of reaction to them.
And as mentioned, porn almost certainly does play a part in things. Not just in the other sizes on display, but the level of reaction to them.