People on their Cell phones

HEY EVERYONE.... Have you ever been in a public place in which were you are standing beside someone and they are talking on their cell phones?  Well I have.. and it is freaking annoying! I mean common when a person is  talking on their cell phone that is what they should be doing.. talking.. not YELLING.  I mean I can understand if it is loud in the surrounding area, but common They make smaller phones.. and the mouth piece is further away from your mouth, but that does not mean you need to scream into the phone just for the other person to hear you.. I mean C'mon!  Who agrees with me on this..?
my mom is a person who does this.. She can be downstairs on her cell phone, and I can be upstairs listening to my music (not too loud, just loud enough to hear) and she is literally screaming on her cell phone!.. Is that really necessary?? Well.... I have been on the other side of that conversation before.. and it is not pleasant for me either.. I cant hardly understand a word they are saying, and I have to have my phone 3 feet from my ear just so I don't blow my ear drums.. Common people Stop screaming into your cell phones!... or get a bigger phone so you feel the need not to yell!....ooh and don't even get me started on Bluetooth!