I doubt if its actually classed as "discrimination"...I wasn't aware being childless made you a "protected class"... I don't have kids either...but these offers take nothing AWAY from me..... so I don't care.
Getting bent out of shape because some little extras are offered to others but NOT to you sounds like a recipe for unhappiness. Do you get annoyed when veterans are offered early boarding? Do you get annoyed when standing on a full train and the woman next to you gets offered a seat, and you do not?