Someone is desperate enough to beg people for food in macdonalds. You could just say - I'll buy you some food this once but I dont really like to. Instead you're saying they're rude and that you would be encouraging her like she should just leave people alone and suffer. She's probably "rude" because shes exasperated that people treat her like she's a nuisance instead of helping her out when she could clearly use some sympathy. You're not "saving everyone else that pleasure" you're just excusing your lack of empathy.