Zachary found the reason why Google decided to discontinue click-to-call in Google Maps and sent this illustrative dialog.

Prankster goes to Google Maps and searches for Bob's Pizza. Then he clicks Click-to-Call and enters 987-654-3210.

Owner of 987-654-3210 [John] (picks up ringing phone): Hello? This is John.
Bob's Pizza: Hello, thank you for choosing your local Bob's Pizza, now offering free delivery. Would you like to place an order?
John: Um... excuse me?
Bob's Pizza (louder and clearer): Would you like to place an order for a pizza?
John: Er... who is this? I think you um ... have the wrong number ...
Bob's Pizza: You called Bob's Pizza. This is Bob's Pizza.
John: What... when did I call... huh... [mutters on]
Bob's Pizza: Sir, you called us not long ago. Please don't try to trick me and say that I called you. I have better things to do.
John: No really, you called me. My phone rang, and I heard your voice! You called me!
Bob's Pizza: You called me!
John: You called me!
Bob's Pizza: You called me!
John: You called me!
[call goes on for several minutes in a similar fashion]
Bob's Pizza [angrily]: That's it, this is a total waste of time. [curses several times] I've had enough of you! Goodbye! [hangs up violently]
John: No! Wait! Really! [hears dial tone]
John [to self]: Oh no... what is wrong with me... I don't drink... I must have gone mad! I need HELP!!! [runs out of house and checks self into rehab]</img> </img> </img> </img>