It’s difficult being an entertainer in Korea. Their contracts are known to be so long and extreme that in some cases they’re called slave contracts. Many idols are on crazy diets, they work long hours, and sometimes though not always it’s for little to no pay (charity concerts, etc.) While there are some people out there such as veteran actors who hate idols, I have no problem with crossover idol actors.
Maybe it has something to do with how I started watching dramas in the first place (Japanese idol dramas to be specific) that I feel they kind of go with the territory. I feel there are also plenty of positive things that come with idol dramas. It gives additional promotion for a drama (especially internationally). It enhances the soundtrack for the drama since many of them sing in the dramas.
For the idol it gives the entertainer an additional income and likeability. But they have to be able to convincingly act. (A smexy face and awesome voice do not exactly cut it!)
Moreover, they have to be allowed to act. Some companies put restrictions on their members. A famous example of this is Dara from 2ne1 who just recently was allowed to return to television after 6+ years away (she was discovered as an actress in the Philippines).
Some have gone beyond the call of duty proving their abilities (ex: Mickey YooChun and Yoon Eun Hye both idol actors ended up in the hospital filming Missing You). Some actors have also turned the tables and become singers with their acting fame (Lee Min Ho, Jang Geun Suk, and Ailee for example). Though really, some should just stick to one thing (I’m talking about you Gu Hye Sun!)
Really everyone should be able to exert their creativity however they choose, be it acting, singing or whatever floats their boat! And we will be there waiting to watch them go!