Usually if I notice a user asking questions with a low Accept Rate, I'll post a friendly comment reminding them that they are more likely to get answers if they improve their Accept Rate by accepting answers to previous questions
A high Accept Rate is a sign that the user is likely to reward those who answer with reputation, and it is more worthwhile to answer them if you're after rep.
The Accept Rate only shows up after the user has asked a few questions, so typically I don't bother asking for someone to accept an answer unless they have a track record of asking many questions without accepting answers
Here's an example of the sort of comment I will occasionally leave for users with a very low accept rate.
And don't forget, the option to accept an answer isn't going to go anywhere. I once left a comment on one question prompting the user to improve his Accept Rate so he could get better answers, and a few minutes later I received 15 rep for an answer I had posted to one of his questions months ago!