Having your needs met and receiving a salary are not the same thing. When Jesus sent out the disciples in pairs and told them not to take anything along, He wasn't sending them out to get paid.
I think it IS the same thing, although I would allow that the life of a Pastor/elder be a frugal one. I think that the intent of the passage (and the passage in 1 Corinthians) is that your living is made "by the gospel." That is, that all the needs of you and your family are met, to the point that you do not have to work another job. Food, shelter, transportation, etc., should be provided by the assembly, so that the person can devote themselves to full time shepherding and preaching.
I think that passages such as Acts 20:33, would demand conversely a life of frugality for the pastor. I have seen churches where the pastor is driving a fancy new car, for instance, when one cannot be found among the congregation. Personally, (personal information alert!) I drive a 12 year old car, have a salary of 22k per year, and am provided a parsonage in which to live. That's it. And my family of four makes it on that. I COULD get another job, so that we could "live large", but I believe that would violate the heart of the command in 1 Corinthians 9, that our efforts should be devoted to the Gospel and missions.
That begs the question, is it salary being spoken of? Context would allude to it being double the gifts received of widows. The widows were not on staff.
Actually, I would say that the context is that the elders who rule particularly well, are being paid double the salary of those who rule less well. I would say that it is a salary, of sorts, that provide for the needs of the pastor and his family. It is a "timae" (payment) given out of the weekly offerings.