Why am I being charged minutes against my account for calling voicemail?

Also, suddenly i'm getting spammed by telemarketers that I did not have any contact with EVER.  This is also being charged against my minutes used. 

I'm considering buying out my contract with verizon and obtaining a plan that is only $45.00 a month unlimited talk, unlimited text, unlimited data.  I'm being charged 120.00 by Verizon Wireless.  I"m only getting 450 minutes a month.  unlimited text and a $30.00 data plan.   I really don't think Verizon services are worth 3x that of other carriers, especially when I am being charged minutes for calling voice mail for Gods sake.    This is ridiculous.  I feel i'm being violated, overcharged, and totally screwed.

I know many people with other companies paying only 39.99 to 45.00 a month unlimited everything.  They don't have any problems with service.