Possible: Sometimes
Why? Why indeed. SOAPs are made to grind, Nike airs may have a plastic small arch part, but it's ussually really small, and not meant for grinding on. Get some SOAPs, they are way more comfertable than Nike Air Max anyways (i know from experience, i had Nike Air Max's before I got my SOAPs, my feet used to hurt, but when I got my express, no more pain).

plus, Soaps look cooler

i know its dangerous but im so phsyced about grinding.

If u wait till a wooden bench is drenched u can usually slide across them with out soaps, i did it at:
http://youtube.com/watch?v=Wohut07VALw

I live in the U.K. also at my School we have 2 wooden rails.

lol sapauthor "possible. why? why indeed! soaps!" lol A+ buddy.

I soaped in my vans after it snowed once. (my vans are my "i don't give a shit" shoes. so if i'm going somewhere snowy or something, i don't wanna damage my soaps, i use my skate vans.) but i had my now messed up PR out side and it had snow on it, and i was like "hm..." so i just tried it and soaped...there was NO lock on and tweaked tricks were IMPOSSIBLE, however, kind grinds mizous (sp?) where awesome...for a few seconds before that "no lock on" factor stepped in and i had to bail.