Certain types of adblocks are "blocked" on kissnaime (Some website in general put a massive png telling you to turn off adblock). More obscure ones like ublock origin aren't blocked thankfully. I do have to admit the settings of ublock origin can be quite confusing, and I haven't been able to set up a whitelist because of it. But do like to use it as i've never seen an ad ever slip through ever since I first started using it.
Kissanime does sometimes detect that I am using a type of ad blocker but refreshing the page fixes that. The ads from kissanime can attempt to put viruses/malware/whatever onto your computer if you're not careful, I'd rather be on the safe side and not risk on accidentally clicking on one. There are no plugins you can get on your phone so using kissanime on your phone isn't very viable if you want to avoid those sorts of ads.
It is safer to pay for a subscription to crunchyroll but like others said, the selection can be quite limited due to the fact they have to pay for licensing for each country. This means we generally get the short end of the stick and have an even smaller selection than America. Of course you could have a VPN but that still a pain and cost money as well.
Haven't checked out how big is animelab's collection of anime but I'm pretty sure its Australian/New Zealand based so their collection shouldn't be as limiting for us.