Moderation is Key
"O People of the Scripture, do not commit excess in your religion..." (Qur'an 4:171)
"Say: 'Call on God or call on the Almighty; by whichever you call on, to Him are the best names.' And do not be too loud in making your contact prayer, nor too quiet; but seek a path in between." (Qur'an 17:110)
"O children of Adam, take your adornment to every mosque. Eat and drink, but be not excessive. Indeed, He does not like those who commit excess." (Qur'an 7:31)
As we see from the verses above, extremity in many things are bad, even when it comes to religion. Almost everything we do has a limit, one must try to not pass that limit.
A lot of everyday things like eating, playing, or working should be done in reasonable magnitudes (moderation). Take for example water or oxygen, both are vital to the existence of humans. But, if taken in extreme amounts, they can be dangerous.
"A Love That is Excessive"
"And you love money, a love that is excessive." (Qur'an 89:20)
From the verse above, we can see God does not condemn the loving of money in itself, but rather the extreme loving of money to the point where they forget their religious duties. To the point where they worship money. To the point where justice and good works are abandoned just for more bucks in the bank. They are those that do not thank God for money. They are those that love money more than God, the One who gave them the money.
Islam: The Balanced Simple System of God
God made the system of Islam easy for us, and He does not wish to burden us:
"God does not want to place any hardship on you..." (Qur'an 5:6)
"God does not burden a soul except with what it can bear." (Qur'an 2:286)