I worked in wireless for several years, well before the smartphone implosion and the need for data plans, phone insurance / replacement, etc. I can honestly say that yes, sales force staff are incentivized to sell specific kinds of hardware based upon marketing initiatives and the like. The equipment could be inferior and less desirable than the brand they are more accustomed to selling but they will have to work their tail off to sell it like it's the greatest thing since sliced bread, even if sliced bread is sitting next to it.
It's the consumer's job to educate themselves on the products available. Research, evaluate, comparison shop, and go into a store only if you need an up close demonstration. You need to vet things for yourself and follow the trust but verify mantra. Yeah, I trust that people have been as unbiased as they could be in reviewing the Lumia 640 XL, but I like to temper some of the fanboyism by actually going into a store and seeing what the fuss is about myself. The phone is huge. Don't get me wrong, there is a reason why they made it that size. Consumer demand. It appears to work for many, and I may eventually be one of those people.
Sales Associates are being trained to be too pushy. Back when I worked retail and started down the same path I had a manager tell me that my approach was anything but sincere and I was risking my job by forcing people to buy into my opinions. I think when I left retail I had gone from various forms of Monty Hall (let's make a deal) to you will buy this from me and like it to finally settling into the routine of asking questions and building a relationship with the customer. If I knew what they wanted, I resisted the easy way out and asked more probing questions to make sure that my answer was truly right (and right for the customer) versus what was right for the store. Granted, this wasn't making me a stellar salesman that could live off commissions alone but I could live with myself. Fortunately I didn't have to live off of my commissions and never took a job outside of high school that paid out commissions. I think that in turn made me a more customer-focused employee rather than a numbers / revenue kind of guy.