You are basically allowing the oil company to have the primary term (the one they negotiated) and the additional time for the same price. That means that if activity increases or prices increase or some other world event you are not able to take advantage of the change. Options, like all other terms in a lease is a choice. We should not make blanket statements because every owner must decide for themselves. I have just never liked being tied down. I want to always have options for myself not the other side
One factor in allowing is whether you are in a proven area. If in a speculative area there is more argument for allowing an option but try to get a higher price for the option to give them an incentive to develop during the primary term.