I installed some apps like this (not Home Depot specifically) because they bribed me to do it. The first item you buy via the app is often a bit cheaper than the price you get on the website.

It's a great way to find out how much you value your own time. Apparently, my time is worth significantly less than what I charge my clients :)

They probably offer "rewards" or discounts for giving them access to your data.

The app is actually a pretty good one, but that doesn’t excuse a 200mb cache (which is probably product images mostly).