I personally would find the sign off putting. Like people have said above me, I have a checklist on my phone of my collection. If I was using my phone to check online prices it would be to double check that I am not going to pay way too much. I have a general idea of prices usually, and I don’t mind spending a little bit more in person to get the item right away locally. My point is if this store frowns on people checking prices on their phones, they must be asking way too much.