It adds up

Sometimes I wonder why people would be okay with buying lunch every single day. No, they are not that expensive but it adds up day after day. I would much prefer to bring my own lunch (much less costly) and spend my hard earned money on clothing, makeup, mortgage...etc. I am sure any logical mind would claim that this is much smarter but I do feel bad turning down invitations to 'get lunch' except special occassions.

should I be embarrassed that I don't have extravagant luncheons?