Cheap? Yes, if you come from a country like the US, UK, Germany, etc. The problems is that salaries for tech jobs aren't very good compared with said countries.
But it's much cheaper, so why is it a problem? Why do you need to earn a salary to pay for a E4.50 coffee if you buy it for E0.50? It's only a problem if you earn much less than other countries but your expenses are the same, right? I mean Lisbon is expensive compared to other cities in PT, but wages are also higher to compensate. They are not 'high enough' (with the '' to say ofcourse they are never 'high enough', but you know what I mean?)?
We decided not to go to Lisbon because of the sheer amount of 'jumpers' (I don't know the proper term): people who will go to another company for E100/month more (probably because there is so much choice there). It's too hard to filter them out and we don't want them. We tried it for a bit but people coming to interviews with proposal letters from other companies in hand to get you to outbid is just not what we want. It's like cheating; you'll know they'll do it again.