Merrel MOAB II mid-highs lately. I also have Timberline Pro's that are pushing 20 years and some newer Red Wings. Footwear is so personal as we all have different needs in that area. I have wimpy feet and have struggled with footwear as long as I can remember. I only mention this to give you my frame of reference / experience. Even a decent sneaker will do me as I have pads in places where I stand for periods. I don't hold very still in the shop and have no shop stool as they are just a waste of space.
I do stand at the bench, assembly areas and even the tablesaw, bandsaw or router table for periods of time and so have thick foam pads in those areas. The ones I use are from Sam's Club and intended as playroom or workout room flooring. I no longer see the product online but do find it still in local stores.
The product has been in near constant use for over a decade (except for the last 2 years while I have been between shops) and show little wear. The new shop will be larger but I have a couple of unopened packs that should take care of that. I would not want to work long on a concrete floor without some sort of pad or high end footwear.