If my friend cared about birthdays (btw, nice job of way over exaggerating the Fi opinion of birthdays :p), I'd respect it. The thing is, it would be a HUGELY personal gesture for me, tailor fitted for that friend specifically. My Birthday loving Fe friend would miss all that undertone, thinking it's just a sweet expression that I do for everyone. In fact, a friend that notices that it's out of character receives huge bonus points.
I think it's nice when someone remembers my birthday, but I don't expect it. I often have a hard time mustering enthusiasm for it, as well, because I don't know if it's *me* they are celebrating, or the social protocol that says that birthdays are a good time to make an appropriate gesture.
I operate on the 'treat others as you want to be treated' theory, and assume others do the same. If someone calls me for my birthday, I sort of assume they would appreciate the gesture in return, so I make an effort. If I forget, I apologize and tell them the truth - I'm not very good with birthdays, nor do I expect them to remember mine. That usually opens up a conversation where greater understanding is reached. If I notice it really means alot to them, I try *much* harder in the future to remember.
Same with other classic Fe gestures. If I don't 'get it', I show appreciation, then try and understand the deeper meaning behind the gesture. This allows me to either return the gesture verbatim, or find a new and creative way to express the same feeling.