Enjoy the luxury of

Hi,

Can you tell me what "enjoy the luxury of sales resistance to items" means? I don't know what luxury here means.
What is a house brand? Does not a house brand make ads for its brand?

Avoid luxury buying or purchasing non-essentials. A Rolex watch does not keep better time than a $15.00 Casio. Enjoy the luxury of sales resistance to items without which you can live a normal life. Buy house brands rather than nationally advertised brands. Guess who pays for the national advertising? You save that when you buy items with the store’s own name.

Thanks a lot