Using AdWords Editor? Read this....

Kind of funny...unless of course you're one of the people making the mistake:-)

Via Micromag...a knowledgeable AdWords dude from Brazil;

"A lot of AdWords Editors users around the world are adding the "Max CPC" keyword accidentally to their groups.

When using AdWords to reorganize my adgroups, I noticed that you can copy and paste a group of keywords from one adgroup to another adgroup by clicking the "Add Multiple KeyWords" before Pasting.

But you need to remove the following header:

Max CPC Keyword Type Keyword Destination URL Keyword Status Comment"

In the rest of the post he goes on to list a few examples where people are inadvertently bidding on the keyword "max cpc" to sell products like loans an vacuum equipment.

If you're using the AdWords Editor you may want to double check your account.