Damn, they're persistent

I have call display, which means I don't ever have to deal with telemarketers. But it also means that some telemarketers are persistent: when I don't answer the phone, they keep trying.

During the last couple of days, I've gotten a bunch of calls from a newspaper call centre and from a 1-866 number. Here are the call times for each:

Newspaper call centre:
July 17, 12:41 p.m.
July 17, 5:50 p.m.
July 18, 9:53 a.m.
July 18, 4:27 p.m.
July 18, 6:34 p.m.

1-866 number:
July 17, 2:57 p.m.
July 18, 10:15 a.m.
July 18, 3:39 p.m.
July 18, 7:20 p.m.

I'm willing to outwait them as long as necessary, but I hope that some poor minimum-wage earner isn't being forced to keep calling me until I answer. Or, worse still, isn't going to get paid until he checks everybody off his list.