Taking advantage of liquidity provided by liquidity pools on SDEX

Question

I'm trying to benefit from the liquidity made available by liquidity pool when I trade, I'm not trying to participate in liquidity pools (I'm not trying to put my money in the pool).

On the xlm/USDC market, I see quite the spread before there is decent liquidity, so I assume the liquidity pool is not making orders as a maker, given it has $4.5M in its pool (am I correct to assume that?).

The doc is a bit unclear regarding how to take advantage of that liquidity. It mentions path payments, without much explanation about how they relate to liquidity pools. So I implemented path payment in my wallet anyway to see if that would do the trick, but it didn't : making a strict send path payment gives me the exact same average price than if I was filling the orderbook. Is there anything special I need to do to buy from liquidity pools?

For reference, here is the code I use:

package horizon

import (
    "fmt"

    "github.com/stellar/go/clients/horizonclient"
    "github.com/stellar/go/keypair"
    "github.com/stellar/go/network"
    "github.com/stellar/go/txnbuild"
)

func PathPaymentStrictSend(sendAsset, destAsset txnbuild.Asset, sendAmount, minAmount, to, secretKey string, path []txnbuild.Asset) (err error) {
    kp, err := keypair.Parse(secretKey)
    if err != nil {
        return
    }
    ar := horizonclient.AccountRequest{AccountID: kp.Address()}
    sourceAccount, err := client().AccountDetail(ar)
    if err != nil {
        return
    }

    op := txnbuild.PathPaymentStrictSend{
        SendAsset:   sendAsset,
        SendAmount:  sendAmount,
        Destination: to,
        DestAsset:   destAsset,
        DestMin:     minAmount,
        Path:        path,
    }

    params := txnbuild.TransactionParams{
        SourceAccount:        &sourceAccount,
        Operations:           []txnbuild.Operation{&op},
        Timebounds:           txnbuild.NewTimeout(30),
        IncrementSequenceNum: true,
        BaseFee:              myBaseFee,
    }

    tx, err := txnbuild.NewTransaction(params)
    if err != nil {
        return
    }

    tx, err = tx.Sign(network.PublicNetworkPassphrase, kp.(*keypair.Full))
    if err != nil {
        return
    }

    if PROD {
        _, err = client().SubmitTransaction(tx)
        if err != nil {
            printError(err)
            return
        }
    } else {
        fmt.Printf("Pretending to transfer %s %#v to %s as %#v\n", sendAmount, sendAsset, to, destAsset)
    }

    return
}