Even at 20 cents a minute, it's tolerable.
Say I run up $30 in calling charges while on a 2-week trip. First of all, you're spending too much time on the phone because if you're making 150 minutes of calls, maybe you shouldn't have gone on that particular trip.
There are some countries where the per minute charges on even a prepaid SIM isn't much better.
Even if I could get a SIM which charges 3 cents a minute including calls back to the US, I don't know if I'd bother swapping SIMs because of the hassle of dealing with a foreign number.
Best thing is to avoid having to call altogether. Use texts if you can. Some hotels used to have Skype. But in the developing world, a lot of them have WhatsApp or Viber or one of the other web-based messaging.
I don't often go to restaurants which require reservations. Hopefully they have online reservations at least.
Now I will buy data SIMs for my iPad though. Often mobile data can be much better than whatever Wifi you get in a hotel, either the large chain hotels or the smaller local ones.