Could definitely be the case. Cases that are made specifically for any model phone, sometimes are good, sometimes not. Same thing for universal, or aftermarket ones.
But I am definitely a firm believer in keeping the phone pointing straight up for two reasons : preventing the phone from accidentally falling out of it and having the antenna pointing straight up for maximum reception.
I'm not a big fan of the leather cases that your phone goes in and stays in. They inhibit certain features and I've found that they can also leave distinguishable, undesirable, marks on your phone.
What model Motorola is your phone?
One cool site that seems to have good deals is
cell phone accessories - Nokia, Motorola, Sony ericsson, Samsung, LG, Nextel, Sanyo, Kyocera, Audiovox accessory They seem like they get you maybe a little bit on shipping, but the selection seems really good.