When you receive a letter telling you can get higher credit limit

Yes, I got a letter from Canadian Tire Bank, which shown me that I have been pre-approved for a higher credit limit.
I have an Options MasterCard with them. The credit limit is $10,000 for many years.
Most of the monthly balance is around $1,500. Until last month, I spend over $5,000 with this MasterCard.
My practice to keep my credit record in good standing is pay full balance before due date. Never later.
As a good credit cardholder. The sent me the letter for ask me to increase the limit.
They put three reasons:

  1. You have earned it.
  2. Feel at ease.
  3. Increase your buying power.

I feel it is great to have a higher limit credit card at hand. So I sign in the online account at www.ctfs.com and accept the limit increase.
My risk control policy is to have one higher limit card and other lower limit credit cards. The higher one is to purchase higher priced items, or for big shopping season like Christmas, or for travel abroad.
The one with higher limit is the one give higher rewards/cash back, without annual fee.
The other cards are used for department store purchase or particular purpose. I use Sears credit card at Sears store. I use HBC credit card at The Bay, Home Outfitter, Zellers stores. I use RBC credit at gas station. etc.
To make my own shopping habit, and follow it.