Such fees and packages take two forms.

It's common to be offered deals at the time of booking. If you pick the tab for packages, you can get extras for a fixed amount above the regular room rate. This could be a "romance package" (with sparkling wine and roses); or "two for breakfast"; or, at a resort, access to bicycles, kayaks, floats, and such; or at a tourist destination, admission to a local attraction; or, at an airport, parking while you're away. It's becoming rare, but "Modified American Plan" would provide breakfast and dinner. These extras are all voluntary. I have no complaints about them.

Then there are voluntary recreation fees that you're offered after you arrive, such as beach rental deals at beach resorts. Again, voluntary. No complaints with them.

Not sure how this represents a nit in relation to what I wrote, which was "It should be a lot easier to see destination fees and parking fees on Marriott.com." I think we're agreement here.