Buy in wholesale if you want to make money retailing or if you want to save money. You could also buy enough products to resale to someone else at wholesale. People do it all the time. Many of the large flea markets, organized yard sales, are selling products that were purchased at wholesale so the retail price would be low. So low sometimes that people buy the products to simply sell them again. There are many wholesale opportunities that will drop ship products to customers that order from you if you want to run an online store also. Some online drop shippers will set up your website and handle the transactions for free, all you do is drive traffic to your site.
The benefits of buying wholesale are obvious, you can get stuff cheap to use or sell to make money. Another very important factor is that you can work from home and actually build a business out of it.
Space for your business is cheap now because of high availability if you don't want to run your business from home.
Another way to buy at wholesale is to buy assorted pallets of merchandise from auctions or business that specialize in liquidating. For this you will need to have stepped your game up as it may require a fork lift, truck, dock, and warehousing depending on how serious you plan to get with it.