This isn't an ethics question. It's a property rights question. Even if you don't have mineral rights, the gas company may have to get your permission to run a line under your property. Or maybe not, depending on the laws of your state and your community and the history of the property rights where you live. You need to go to a local real estate development lawyer for advice. Make sure he or she has no ties to the company in question.
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A simplistic way to look at this scenario is as follows. If the well is being drilled pursuant to an oil and gas lease covering the minerals underlying your land, or lands pooled therewith, then the oil company has the right to utilize the surface of the land to the extent reasonably necessary. Accordingly, the payment of surface damages is not required by law, but is fairly common practice. If the unit does not include the minerals underlying your property, then, in most instances, the oil company cannot have access to your property without your consent (or the consent of a cotenant). Accordingly, the facts of the situation will determine the strength of your negotiating position. And yes, almost everything paid in the oil patch is negotiable.
If you do not know the facts of affecting your situation, you may want to hire an attorney or landman to figure them out.