Ozil has talent and was signed from a very good Madrid team but at the moment he is stealing a living like Bale is
When Arsenal signed him I'd only really seen him play for Germany and felt he was a good player, but the reports on him were that he had tons of ability but the heart of a mouse. When the going got tough he would hide and at times you may as well play with ten men. From what I've seen of him since I can only say that assessment was totally accurate.
Same with Sanchez. In a team that is on top, doing well he is an amazing player capable of destroying opposition. But once they fall below that he becomes much less effective and becomes sulky. At Barca and his early Arsenal days they were teams that were often dominant and he showed his ability. When Arsenal started to drop off from that slightly he wasn't having the impact, and more importantly didn't look that bothered about it. Same at Man U.
The point is that these are not players that will likely turn a game in your favour. They will take a game you'd almost certainly win anyway and turn it into a rout. And for me those aren't the players that should be your highest earners. Those should be the ones that can take a game you're struggling in and turn it around for you. Championships are won when you win games you don't play well in. Neither of these two are likely to make that happen because for all their ability they'll either hide away or sulk. And they won't care they're doing it.