Sure, protein shakes might be digested faster, but I'm against processed, I'm for natural. Who knows what essential nutrient is missing in these shakes that comes for free with meat.
If you're not working to actively put on weight or keep it on and you live in the west, you probably don't really need to worry about protein. Even those on plant based diets can get enough.
http://www.pcrm.org/search/?cid=251