I just changed the oil and filter on my bike for the first time (bought used in 0

Why would I need to buy a oil relocation kit? The job only took 1 hour or 4beers!! This was easier than I thought. I only drive my bike about 2000 miles a year or 1600 kms.Can someone tell me why I should spend $400 to have an external oil filter which I would only change once a year, Thanks.