For me, Arrow is best for larger orders, such as full reels of components or largish quantities of semiconductors. However, what seems like excess can make sense sometimes. I ordered a small quantity (25) of op amps a while back (AD812ARZ), and they arrived in several bags, but each bag was a consistent datecode - they didn't just mix them all together. Many places like Mouser and Digikey don't mention the datecode at all, and I think Arrow is oriented to customers that need to keep track of datecodes and the like for traceability.
So, I think Arrow is just trying to work their way down the sales chain to the small guys like us, and what seems excessive sometimes is not really excessive at all. If you think about it, being sloppy about mingling datecode lots is actually the sloppy practice. Sure, for little guys like us who don't have to do traceability, it seems extreme, but I can always trust what I get from them to be genuine and fully specified.
Overall, I like Arrow and I like their promotions. I'll always check them for stock, and especially now with the giant vacuum for some parts like MLCCs, they can have useful stock that other vendors don't have. Overall, I'm a happy customer, and their free overnight is a great thing.