There's absolutely nothing unethical about it whatsoever. There's no reason it should be considered unethical. This is well established within chess circles.
Is recurring check ethical?
<joke>It is totally unethical, just like taking the opponent's queen after you have not warned them by saying "Gardez!"</joke>
[Hoping the tags will prevent me being accused of being serious]
Yeah that's exactly what I was thinking, if you see a weakness you're harldy going to disregard it because your opponent has played much better than you up till that point. Out of over 200 games I've forced stalemate 3 times and I admit 2 times were flukes but only one opponent thought it was cool and fair play, the other two thought I was well dodgy lol. So that's why I was asking because I thought maybe on forums like this it's frowned upon. Thanks for clarifying it for me.
I must admit though I did feel guilty a couple of times because they were flukes and it's quite bad when you've been thoroughly outplayed 
If you are getting slaughtered and find a way to draw via recurring check is it ethical?
I personally think it's fair because it takes a bit of strategy to acheive it and people should make sure it can't happen if they are winning.
Or is it only a thing you should do in a tournament and on chess.com there should be an element of ethical fair play?