I wouldn't say its expensive. Given how much time it saves you (money), the convivence it offers your clients which in turn will increase conversation rates. Its a big win to have. If you are struggling to make profit then then you do need to look at your business plan. I think The price increase does make it a little harder, another thing is competitiveness in hosting which lowers the charge that you can get away with for your service.
If you chase that you wont win.
Try adding some value to your hosting to get a bit more out your clients.
Most website owners will happily pay a little extra for content updates, additions which once a website is up is fairly easy to implement. It keeps their website fresh, meaning better chance of a successful business for them, meaning longer hosting for you. Theres a lot of ways to play this thing out. This current price of WHMCH shouldn't be a deal breaker (IN MY OPINION) .
Laslty transfer the costs over to your clients reasonably, again If you want to soften that blow add some extra value, extra space or whatever.
Everything goes up in price, bread, milk instalments it shouldn't be a shocker for them. Some will leave, but most wont and ill pay the higher rate making up for those who left.