Another explanation, @phoneone, besides what John said above is that beginner traders and intraday traders tend not to put as much emphasis on swap rates as they do other factors such as spreads. Therefore brokers whose primary clientele is beginner traders or intraday traders may offer less competitive swap rates than brokers whose primary clientele is advanced traders or long term traders.
That’s why when choosing a broker, you should consider all factors, not just spreads or leverage, as highlighted by this earlier discussion: Unregulated brokers illegal? Whats the Risk? Help Please!