the blonde & the cellphone

A young man wanted to get his beautiful "blonde" wife
something nice for their first wedding anniversary¹. So he
decides to buy her a cellphone².

She is all excited, she loves her phone. He shows her and
explains to her all the features on the phone. The next day
the blonde goes shopping.

Her phone rings and it's her husband, "Hi hun,"he says "how
do you like your new phone?"

She replies: "I just love, it's so small and your voice is
clear as a bell! But there's one thing I don't understand
though."

"What's that, baby?" asks the husband.

"How did you know I was at Wal-Mart?"