Are they trying to make "let's alipay" a slogan? if that were the case I would definitely agree with you but with a single example it is hard to say for certain either way.
The calligraphic font used for the phrase in question in that advertisement is commonly used for slogans or take-home message in modern Chinese advertisements. The placement of the phrase also suggests that it's a slogan.
Other images from MTR Advertising[1] also seem to suggest that it's the intended slogan of this campaign, too.
[1]https://www.facebook.com/mtradvertising/photos/a.15944807239...