On the one hand it's free work benefiting the corporation... but on the other hand it's genuinely helping sometimes thousands of other people. I benefit massively from reading Amazon reviews, and it feels good to give back. But it is also a contribution that further entrenches Amazon (or Google Maps), it's not like Wikipedia where contributions can be used by anyone.
What do we do when we can help other users, but doing so also supports corporations for free? Although then again, I've never paid a dime for Google Maps and use it daily, it's literally a major part of my life -- so does getting the product for free also play a role?
For example if you wanted to put in your new directory whether company A has a car park at their premesis or has disabled access etc, you would need to pay somebody to either go there and perform a survey or call them up and ask them. Googles monopoly enables them to just ask the question to everybody that has ever been there and get the data returned back into the system automatically and free.
I see this as anticompetitive and so I choose not to participate.
It's harder for map corrections though, as the user-presented data mixes commercial and user-supplied data. Maybe legislation should require regular data dumps of all user-supplied content much like Wikipedia makes available in XML form? Then no scraping is even required.
Contributing to Stackoverflow is my one exception.
On the topic: I think it would be a good idea for OSM if done in a good and non-technical user-friendly way.
I found the "Emergency" door of a local hospital hard to find IRL, so I added a photo of it from the driveway POV. Another sort of real person you can help are the web-clueless owners of local small businesses.
I also enjoy adding a food shot or a representative photo of places I have enjoyed as a small reward and enticement for others to do likewise.