in short no its not cheating,when PVP comes around then yes, it could possibly in a small way be classed cheating, as someone being able to lvl up stupidly fast will affect others of opposite moral code. as is now, someone being lvl 40 when you're lvl 10 doesn't affect you at all EVER, even if he worked his backside off to get there or had one of his friends pl him there. there is no bug there is no exploit, they use game mechanics to do it therefore it is not cheating.
to cheat is to gain an unfair advantage, they are not gaining an unfair advantage as enemies scale up to lvl's a lvl 40 fihting lvl 42 mobs would have a hard time same as a lvl 10 would have with lvl 12 mobs.
frankly they shoulddn't and can't, without screwing up an amazing game, remove powerlvling.
and how it affects you i have no clue, why care??? you got there the right way bully for you, they pay as you do, they could argue in reverse, he took so long to get up to my lvl its not fair, he's boring (granted i doubt they would as thats a lame [censored] complaint)
but then this complaint is lame [censored] and you made it... so who knows