When a mall has no specific area with a bike rack, you can:

a) start a crusade against the property management and bombard them with complaints

or

b) lock to something else (like a signpost).

I don't mind it, and even appreciate it if someone does a) - it's good to have bike parking (though going overboard with this sort of stuff may result in a "bikes prohibitied" sign on the property instead - treat someone like an enemy and he'll start treating you the same way eventually). But I have better ways in which to spend my time, so just do b) and neither I nor my bike are worse for the wear.