When you have no goal of buying an item, it is prudent under no circumstances to bid only for the heck of it. If no one bids after you, you will be required to purchase the merchandise or forever be forbidden from the auction site. Nearly all online merchants accept credit card transactions.
There are people that benefit from online notifications and strive to fraudulently promote fair tips. The truth is they profit from such referrals whenever they are fortunate to persuade folks straight into buying.